Ask the Expert
Inspecting for earthquake damage
We’re planning to buy a home in the next year. After the last earthquake, we’re concerned about hidden damage lurking in homes. How do we decide whether we need a structural engineer to inspect it first?
When buying a home, having a home inspection may or may not be required, but is usually expected. A home inspector will recommend that a structural engineer inspect the home if it is necessary. Things to look out for on your own, so that you can see if a house may be damaged before the inspection stage, include:
- Sheetrock cracks – a general rule of thumb is that lateral movement from earthquake or wind loading causes diagonal cracking over doors and windows. Look for cracks or signs of repairs
- Houses that are out-of-level – uneven floors, out-of-plumb door and window frames or walls
- External sheathing or trim that has popped loose
- Significant cracking in the foundation masonry or concrete (some minor cracking is expected)
Southcentral Alaska is a very earthquake-prone area, so every structure is going to be exposed to earthquakes and may have some degree of earthquake damage. Some areas of the state are more earthquake prone than others, and some structures are less able to resist earthquake and/or wind damage. To make sure your home has significant structural capacity in the event of an earthquake, avoid:
- “Great rooms” or any large, open space with significant window walls and the lack of supporting walls or columns
- Poorly reinforced masonry chimneys
- Poorly attached masonry or brick veneers
- Large log structures
- Homes built in areas with unstable or shifting ground conditions, like steep slopes or organic rich soils
- Homes built on sandy soil with a shallow water table
A good resource for an indication of existing soil conditions and site slope stability is the “Foundation and Excavation Conditions” map available for viewing at the Municipality of Anchorage Building Department.
Always remember that no house is perfect. A buyer being happy with a home has a lot to do with the need for perfection and the ability or resources to deal with the problems.
